fix inference when no chat_template is set, fix unsloth dora check (#2092)

* fix inference when no chat_template is set, fix unsloth dora check

* remove old unsloth version check

* update docs on installing unsloth

scripts/unsloth_install.py

@@ -0,0 +1,33 @@
+# noqa
+# pylint: skip-file
+try:
+    import torch
+except ImportError:
+    raise ImportError("Install torch via `pip install torch`")
+from packaging.version import Version as V
+
+v = V(torch.__version__)
+cuda = str(torch.version.cuda)
+is_ampere = torch.cuda.get_device_capability()[0] >= 8
+if cuda != "12.1" and cuda != "11.8" and cuda != "12.4":
+    raise RuntimeError(f"CUDA = {cuda} not supported!")
+if v <= V("2.1.0"):
+    raise RuntimeError(f"Torch = {v} too old!")
+elif v <= V("2.1.1"):
+    x = "cu{}{}-torch211"
+elif v <= V("2.1.2"):
+    x = "cu{}{}-torch212"
+elif v < V("2.3.0"):
+    x = "cu{}{}-torch220"
+elif v < V("2.4.0"):
+    x = "cu{}{}-torch230"
+elif v < V("2.5.0"):
+    x = "cu{}{}-torch240"
+elif v < V("2.6.0"):
+    x = "cu{}{}-torch250"
+else:
+    raise RuntimeError(f"Torch = {v} too new!")
+x = x.format(cuda.replace(".", ""), "-ampere" if is_ampere else "")
+print(
+    f'pip install unsloth-zoo && pip install --no-deps "unsloth[{x}] @ git+https://github.com/unslothai/unsloth.git"'
+)